Insulating glass (IG) window units typically include first and second glass substrates spaced apart from one another via at least one spacer so as to define a gap therebetween. For example, see U.S. Pat. No. 5,557,462. The gap between the glass substrates may or may not be evacuated and/or filled with gas in different instances. As in the '462 patent, one of the glass substrates of the IG window unit is often coated with a solar control/management coating (e.g., a low-E coating). Solar control/management coatings typically include at least one layer (e.g., of or including Ag, Au, NiCr, and/or the like) that reflects infrared (IR) and/or ultraviolet (UV) radiation. Example solar control/management coatings may be found, for example and without limitation, in any of U.S. Pat. Nos. 3,682,528; 4,898,790; 5,376,455; 5,377,045; 5,514,476; 5,557,462; 5,688,585; 5,770,321; 5,902,505; 5,942,338; 6,059,909; 6,060,178; 6,132,881; or U.S. Pat. No. 6,159,607.
IG window units are typically made in the following manner. A first glass substrate is coated (e.g., via sputtering or the like) with a solar control/management coating, and processed as follows. The coated glass substrate may be shipped (e.g., via truck, train, ship, plane, or the like) from the coating facility to an IG manufacturing facility, and put in inventory using a forklift or the like. Subsequently, a forklift may move the coated substrate from its inventory location to a cut-down line where the coated substrate is cut to size. The cut coated substrate may then be seamed, washed, and heat treated (e.g., thermally tempered). Thereafter, the coated substrate is coupled to another glass substrate via at least one spacer so as to form an IG window unit.
Unfortunately, during the course of such processing between coating and heat treatment, the coated substrate is moved on numerous occasions and is subject to damage (e.g., scratching). Low-E coatings are often soft and tend to be prone to damage in this regard such as scratching. Yields have been found to suffer due to coated substrates which are damaged (e.g., scratched or otherwise rendered non-useable) between coating and heat treatment.
In view of the above, it will be appreciated by those skilled in the art that there exists a need in the art for an improved method of making window units (e.g., IG units, vehicle windshields, and/or the like) which include at least one coated substrate.